The Messenger

One of the most intriguing planets in our Solar System, and also the closest to the Sun of the eight planets orbiting around it, is Mercury. It was named so by the Romans, in honor of the Roman deity Mercury, the fast-flying messenger to the Gods. And really, the time interval it takes Mercury to complete its orbit around the Sun is only 88 days long, much faster than any other planet. That means one year on Mercury lasts for 88 days, as opposed to 365 days, the length of the year on Earth. Also, one day on Mercury lasts 176 Earth days. How is that possible?

Mercury in Accentuated Color

Source: http://apod.nasa.gov/

Because it is positioned so close, Mercury is almost tidally locked to the Sun, whch has over time slowed the rotation of the planet around its axis, nearly matching its orbit around the Sun. In terms of size, Mercury is the smallest planet in the Solar system, with a diameter of just 4,789 kilometers, compared with 12,742 kilometers, which is the Earth’s diameter. Although small, it is really dense, due to the fact that it mainly consists of heavy metals and rock. Being so close to the Sun, Mercury is very difficult to see, not only with a naked eye, but even through the telescope. Surprisingly, even though it’s the nearest to the Sun, it is not the hottest planet in the Solar System. Despite being furhter from the Sun, Venus experiences higher temperatures. One of the defining characteristics of Mercury, is that its atmosphere is virtually non-existent, because it’s very thin, created by atoms blasted from the surface by solar winds. Those atoms, containing hydroden and nitrogen, escape rapidly into space, effectively rendering a normal atmosphere impossible. Among other conditions that occur on its surface, is the extreme difference in temperature between the highest and the lowest value, measuring as high as 427 degrees Celsius on the side of Mercury that faces the sun, and as low as -173 degress Celsius, on the alternate side. This is due to the planet’s lack of atmosphere, which plays a crucial role in temperature regulation.

As we mentioned earlier, because of its proximity to the Sun, Mercury is very difficult to see and visit. As a matter of fact, a trip to Mercury requires more fuel than the trip outside the Solar System. During 1974 and 1975, Mariner 10 flew by Mercury three times, mapping about 45% of its surface. The planet wasn’t visited again until the Messenger probe was launched in 2004.

A Spider Shaped Crater on Mercury

Source: http://apod.nasa.gov/

In many respects, Mercury is similar to the Earth’s Moon. Its surface is covered with a multitude of craters, which are formed mostly by frequent encounters with asteroids and comets. Depending on which side of the planet you were to stand on, you might experience some unusual effects. On the brighter side, the Sun appears about two and a half times larger than it does on Earth. If you were to stand on the opposite side, you would be able to see billions of stars.

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